The present invention relates to a mobile wireless communication technique and more particularly, to a system parameter setting technique in the mobile wireless communication system.
As a mobile wireless communication technique is advanced, a bit cost is being reduced. When a shift is desired from an existing system to a new system or when a new system is introduced while also maintaining an existing system, it becomes important to reduce an initial investment cost, introduce the new system more smoothly, and start the service of the new system more quickly. In order to remarkably reduce the initial investment cost, its key point is to utilize the resources of the existing system as much as possible. For example, use of a power supply or a frame in the existing system can lead to highly effective reduction of its initial cost. An example of such techniques of utilizing an existing system is disclosed in a magazine entitled “FUJITSU” 2007 March (Vol. 58 No, 2), Special Supplement 1:3.5 Generation Mobile Communication Base Transceiver Station for HSDPA (http://img.jp.fujitsu.com/downloads/jp/jmag/vol58-2/paper 03.pdf).
In mobile communication, meanwhile, such a handover mechanism as to maintain a communication continuity even when a mobile terminal is moved across different base stations, is already established so that the mobile terminal can be freely moved within the cover areas of the base stations. For the purpose of attaining handover, a reception signal power of a signal transmitted from a base station being now connected to the mobile terminal is compared with reception signal powers of signals transmitted from a plurality of adjacent base stations (searching). The searching of the adjacent base stations imposes a heavy processing load on the mobile terminal. In order to avoid it, in a mobile wireless communication system, there is generally introduced such a mechanism that fundamental information (base station identifiers in physical layer) of the adjacent base stations called a neighbor list is informed from the base station to the mobile terminal. The mobile terminal can reduce its searching load by inviting searching range on the basis of the neighbor list received from the base station.
In the prior art, the neighbor list is designed mostly by human work such as measuring of the actual propagation state based on computer-aided propagation simulation, operating experimental tests or the like. Thus creation of neighbor lists of tens of thousands of base stations installed in order to cover a vast area results in a highly large number of steps and a lot of time.